The present invention relates to stationary seal wall structures designed for use in high temperature applications such as jet turbine housings which provide a stationary seal around the rotating rotor blade tips or shroud to restrict the amount of intake air therebetween. In such applications it is important that the wall structure be as close as possible to the rotor blades or shroud since the gap increases during operation due to the increased thermal expansion of the wall structure relative to the turbine blade structure. An increased gap can result in an increase in fuel consumption and/or a decrease in engine power. Thus, the wall structure must be abradable to prevent damage upon possible contact with the rotating turbine blade structure during initial start-up and prior to thermal expansion. Also it is desirable to reduce thermal expansion of the wall structure, such as by cooling thereof, and to reduce the erosion and/or corrosion of the surface of the wall structure in the gap in order to prevent increases in the gap width due to loss of material from said surface during use.